高温熔融盐基纳米流体的研究现状及进展

State-of-the-art Review on High Temperature Molten Salt Based Nanofluids

熔融盐是目前高温储热领域应用的重要蓄热材料。强化熔融盐的热导率和比热容可以提高系统效率和安全系数,减少储热材料用量,进而降低储热系统成本。向熔融盐中添加少量纳米颗粒形成熔盐基纳米流体可以显著提升熔盐基液的热导率和比热容,是近年来高温储热领域的研究热点。通过对相关文献进行梳理和分析,具体阐述熔盐基纳米流体的制备方法,从实验研究、数值模拟研究、理论研究等不同维度,重点介绍纳米颗粒对基液热物性的强化效果、强化机理、经验预测模型及对机理的验证情况等问题。此外,简述纳米颗粒对基液黏度影响的研究现状。同时,重点探讨制约熔盐基纳米流体大规模应用的瓶颈—稳定性的研究现状。最后,基于研究现状进行分析,指出此项技术需要进一步研究和解决的问题,以期为熔盐基纳米流体的发展和实际应用提供有价值的借鉴和参考。

Molten salt is an important thermal energy storage material currently used in the field of high temperature thermal energy storage. Enhancing the thermal conductivity and specific heat capacity of molten salt can improve system efficiency and safety, reduce the amount of thermal energy storage material, and thus reduce the heat storage cost. Adding tiny amount of nanoparticle in the molten salt to prepare molten salt based nanofluid can significantly enhance it’s thermophysical properties, and this technology is also a research hotspot in the field of high temperature thermal energy storage in recent years. Based on the analysis of relevant literature, the preparation methods of molten salt based nanofluid were introduced, moreover, the thermophysical properties enhancement, mechanism, empirical prediction models and verification of mechanism were explored in details from experiment, numerical simulation and theoretical research. In addition, the nanofluid viscosity was also introduced in this paper. Furthermore, the research status of stability, which is the bottleneck restricting the large-scale application of molten salt based nanofluids, was mainly discussed. It is believed that this review could provide some valuable references for the development and practical applications of the molten salt based nanofluid technology.